The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech has achieved the Year 2 goal of producing a 65% functional mule vehicle suitable for testing and refinement, while maintaining the series-parallel plug-in hybrid architecture developed during Year 1. Even so, further design and expert consultations necessitated an extensive redesign of the rear powertrain and front auxiliary systems packaging. The revised rear powertrain consists of the planned Rear Traction Motor (RTM), coupled to a single-speed transmission. New information, such as the dimensions of the high voltage (HV) air conditioning compressor and the P2 motor inverter, required the repackaging of the hybrid components in the engine bay. The P2 motor/generator was incorporated into the vehicle after spreading the engine and transmission to allow for the required space. This spreading of the components meant a redesign of the front powertrain mounts and integration of a torque damper as an interface with the combustion engine and P2 motor. Furthermore, the Energy Storage System (ESS) was redesigned to include the 5-bar replacement structure within the battery support structure.
HEVT has spent a large amount of time in algorithm development and testing such as modeling the soft- ECUs of vehicle components and physical plant model concurrently with the control code. The team then advanced to Software-In-the-Loop (SIL) testing with iterative code and model modifications. Once SIL testing was complete, Hardware-In-the-Loop (HIL) testing began. At this stage, the team ensures a robust control strategy by introducing faults to see how the controller handles different situations. Only after these tests are complete does the team conduct in-vehicle testing. Overall, HEVT has integrated all necessary hybrid components and developed a robust control code to complete their EcoCAR 2 Year 2 Chevrolet Malibu.